struct field data type improvement for memory usage.

bench_str.csv

@@ -526,3 +526,14 @@
 1400923315,10840939.91,4663256.98,55924.05,2611667.47
 1400923325,11091416.01,4103660.70,59074.70,2817256.97
 1400923335,11435046.07,4356917.52,45100.04,2883103.51
+1400928121,11717285.79,4816672.70,58254.22,2897866.52
+1400928131,11343621.37,4759351.32,45100.04,2849262.65
+1400928141,11268332.55,4717279.18,55188.21,2871378.81
+1400928151,11308055.40,4652350.21,47662.55,2866742.89
+1400928225,10802915.60,4687267.34,58254.22,2632936.94
+1400928235,10661874.62,4739682.52,62601.55,2740810.88
+1400928262,11033784.15,4714416.68,55188.21,2737984.12
+1400928272,10649279.69,4567955.12,47662.55,2716598.01
+1400928308,9831622.81,4277888.23,45590.26,2421364.56
+1400928319,10230059.66,4527332.79,49932.19,2345303.39
+1400928329,11085172.21,4647514.08,62601.55,2735715.15

include/r3.h

@@ -35,13 +35,12 @@ struct _node {
     // almost less than 255
     unsigned char      edge_len;
     unsigned char      edge_cap;
-
     unsigned char    compare_type;
     unsigned char    endpoint;
+    unsigned char    ov_cnt;
+
+    // <-- here comes a char[3] struct padding for alignment since we have 5 char above.
 
-    // almost less than 255
-    unsigned char      route_len;
-    unsigned char      route_cap;
 
     /** compile-time variables here.... **/
 
@@ -51,6 +50,10 @@ struct _node {
 
     char * combined_pattern;
 
+    // almost less than 255
+    unsigned char      route_len;
+    unsigned char      route_cap;
+
     /**
      * the pointer of route data
      */
@@ -60,9 +63,9 @@ struct _node {
 struct _edge {
     char * pattern;
     node * child;
-    unsigned char  opcode;
+    unsigned short pattern_len; // 2 byte
-    unsigned short pattern_len;
+    unsigned char  opcode; // 1 byte
-    bool     has_slug:1;
+    unsigned char  has_slug; // 1 bit
 };
 
 typedef struct {

src/node.c

@@ -196,6 +196,8 @@ void r3_tree_compile_patterns(node * n) {
     int erroffset;
     unsigned int option_bits = 0;
 
+    n->ov_cnt = (1 + n->edge_len) * 3;
+
     if (n->pcre_pattern) {
         pcre_free(n->pcre_pattern);
     }
@@ -254,17 +256,12 @@ node * r3_tree_matchl(const node * n, char * path, int path_len, match_entry * e
     info("try matching: %s\n", path);
 
     edge *e;
-    char rc;
     unsigned short i;
-    unsigned short ov_cnt;
     unsigned short restlen;
-    char *pp;
-    char *pp_end = path + path_len;
-
-    char *substring_start = NULL;
-    int   substring_length = 0;
 
     if (n->compare_type == NODE_COMPARE_OPCODE) {
+        char *pp;
+        char *pp_end = path + path_len;
         for (i = 0; i < n->edge_len ; i++ ) {
             pp = path;
             e = n->edges[i];
@@ -302,9 +299,12 @@ node * r3_tree_matchl(const node * n, char * path, int path_len, match_entry * e
     // if the pcre_pattern is found, and the pointer is not NULL, then it's
     // pcre pattern node, we use pcre_exec to match the nodes
     if (n->pcre_pattern) {
+        char *substring_start = NULL;
+        int   substring_length = 0;
+        int   ov[ n->ov_cnt ];
+        char rc;
+
         info("pcre matching %s on %s\n", n->combined_pattern, path);
-        ov_cnt = (1 + n->edge_len) * 3;
-        int ov[ ov_cnt ];
 
         rc = pcre_exec(
                 n->pcre_pattern, /* the compiled pattern */
@@ -314,7 +314,7 @@ node * r3_tree_matchl(const node * n, char * path, int path_len, match_entry * e
                 0,            /* start at offset 0 in the subject */
                 0,            /* default options */
                 ov,           /* output vector for substring information */
-                ov_cnt);      /* number of elements in the output vector */
+                n->ov_cnt);      /* number of elements in the output vector */
 
         // does not match all edges, return NULL;
         if (rc < 0) {